you need to make sure you’re using exiv2 0.27.4 or later with bmff enabled, update the rawspeed stuff in src/external and integrate pull request #271 or use the rawspeed fork at GitHub - cytrinox/rawspeed at canon_cr3
or get https://github.com/MStraeten/darktable.git - thats the base for my osx & windows builds of current master + cr3